Lighting accounts for almost 8% of the world’s energy usage. It makes up around 10-20% of domestic energy bills, with an even higher proportion in commercial premises like offices.

But it still has huge potential for improvement. Technological changes and management of consumer behaviour can greatly reduce energy consumption without sacrificing comfort – and even improve health and wellbeing along the way.

LED lightbulbs marked a huge leap forward in energy efficiency. They can reduce energy consumption by 50-80% in comparison with older technology, but their impact goes beyond energy savings, as by emitting less heat than older bulbs, they also reduce the need to cool interiors.

Type of light also plays a role in our bodies, affecting sleep, attention and metabolism. But its impact mainly depends on intensity. Bluer light – typically emitted by screens and “cold” LED bulbs – can alter the brains’ production of melatonin, which impacts sleep and circadian rhythms. Warmer and properly adjusted LEDs, on the other hand, can minimise this effect. They are also more energy efficient than other systems.

Better lighting doesn’t mean more light

A typical mistake in interiors is total, uniform lighting. We flip the switch and illuminate an entire space without considering how each each area of it will actually be used. But lighting needs are far from uniform. For instance, European regulations state that a hallway needs around 100-200 lux, while a workstation needs around 500.

Dividing up spaces can reduce lighting energy consumption by anywhere from 20% to 40% without affecting visual comfort. And further savings – as much as 20-60% – can be achieved through smart lighting systems that use sensors to automatically adjust lighting........

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